The present invention is directed toward a method and apparatus for packaging, mixing and delivering bone cement. More particularly, the present invention relates to a method and apparatus for intimately mixing the two or more components of bone cement wherein the components are initially kept in separate compartments of a flexible package.
The natural joints of the human body often undergo degenerative changes due to various etiologies. When these degenerative changes are advanced, irreversible and unresponsive to non-operative management, it may ultimately become necessary to replace the natural joint with a prosthetic device. When such replacement becomes necessary, the prosthetic device which is implanted is often secured to the natural bone by using bone cement.
Bone cement which is used to secure prosthetic devices to bone is comprised of a liquid monomer component that polymerizes about a polymeric powder component. In this regard, bone cement is generally formed from a methylmethacrylate monomer and polymethylmethacrylate or methylmethacrylatestyrene copolymer. The preparation of bone cement generally involves mixing the components in a suitable reaction vessel to form the bone cement. Generally, it is necessary that the components of bone cement be uniformly and thoroughly mixed so that a homogenous product is obtained.
During preparation of bone cement, various vapors are generated which are comprised primarily of the volatilized components of the bone cement. Because of the offensive smell such vapors may have, several evacuation and containment devices have been developed to minimize exposure to such vapors. Despite the advances in fume evacuation and containment during mixing, there has been little advancement in the art of packaging the bone cement to further minimize exposure to the offensive vapors.
Traditional open bowl bone cement preparation may, under certain circumstances, result in porosity in the bone cement product. Several vacuum mixing and centrifugation devices have been developed to minimize this porosity. While effective in the laboratory setting, these devices are complex and difficult to use which results in a variety of cement porosities achieved in the clinical setting. Furthermore, these systems are expensive and create a considerable quantity of disposable waste.
Accordingly, a need exists for a simple and inexpensive bone cement packaging system which will allow mixing of the two or more components while avoiding the above-mentioned disadvantages.